Bolt-anchor.



H. W. PLEISTEH.

I BOLT ANCHOR.

APPLICA .18.1917- l WQ w Patented May 28, 419118.

fw By A7 W M 1 M mToH/l/ y 25 inthe wall, block or other material. rIhis f 'iii 11E l i 11:.

HENRY w. MEISTER, orwns'rriniinnnw JERSEY, Assis-Noa 'ro HENRY is.4 NEWHALL.

BOLT-Antinori.

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Specication of Letters Patent.

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original application inea septemberao, 1916, serial Nannies. Divided and thisappncanon mea september 18,1917. serialivaieiis. i l

To all/whom it may concern: c H

`Be lit known that I, HENRY W. PLEISTER, a

`citizen of the VUnited States, residing at Westfield, in the county of Union and State of New Jersey,4 have yinventedcertain new and useful VImprovements inBolt-Anchors, of 'which the following is a speciiication, taken in connection with the accompanying drawings. y

This application is a division of my copending application, Ser. No. 121,105, filed September 20,1916. l

My invention relates to bolt anchors and more particularly to abolt anchor which has a great holding capacity and yet one which will not crack a wall, a partition, a block of marble, stone or any `other material in which itmay be desired to use my bolt anchor.`

The common formfofbolt anchors are expanded by having theexpandingmember, thc screw or bolt, move down lan inclined surface which extends approximately from one' end to the other, and `which -reaches its nearest approach to theaxis of the bolt anchor at the end which is farthest embedded causes `the maximum expansion to be at the very end of the bolt anchor. This makes it impossible to use the kordina-ry common form of expansionbolt in many locations.

My expansion boltremoves the point of maximum expansion fromithe end"of the bolt and insures a gradually lessening grip and" wedging action from that point to the end of the bolt anchor.

My invention further relates to certain details of construction which will be described in the specification and pointed out in the claims.

I have shown in the accompanying drawings an illustrative embodiment of my invention but ofcourse it is to be understood that my invention is not to be confined simply to, theform illustrated. In these drawings the same reference numerals refer to similar parts.

Figure 1 is a longitudinal vertical section of my invention shown as a one part lag shield having an open side permitting the lag screw to engage directly both with the lag shield and the support;

Fig. 2 is a longitudinal vertical section of the lag shield shown in Fig. 1 mounted in a support and holdingthe work which is also shown in section.

In the illustrative embodiment of my invention 1 is a bolt anchor formed as a one part lagshield 2 having an open side 3, lugs 4, v4, inclined surface 5 whichtapers to a point intermediate itsA ends as for example the point 6 and thenrecedes to the point 7 1" forming t-he Haring surface 26. Screw threads 8, 8 are preferably cast in the lag shield. `I preferably also provide the lag shieldy withan open `unthreaded throat 9,

and with longitudinally` extending `ribs 10 r anchor satisfactorily because the wall or partition 12 is relatively so thin,` that their use will crack or destroy the surface 14 of thewall or partition, thereby giving an unsightly appearance to the wall, if not actually requiringthefservices of a'mason orplasterer totouch `it up or `repair it. `By my invention I avoid "the cracking,`or marring, or breaking. the wall or support 12 `by removing the maximumv strainand wedg- `ing stresses from the point 15 to a point removed from the end 16 of the bolt anchor and far enough away from the surface 14 so as to bring the point of maximum expansion at substantially the point 17, well within the body of the wall or partition 12.

In the operation of my invention, Fig. 2,

the hole 18 is formed in the wall or partition 12 leaving a comparatively thin portion 19. The bolt anchor 2 is then inserted and the work 13, whatever its weight may be, will be heldto the face 20 of the wall or partition 12 by means of the lag screw 21 which will cooperate with the screw threads 8, 8 on the inclined surface 5 and the Haring surface 26 and, at the same time, the male threads 24 of the lag screw 21 will coperate directly with the wall or support 12 and cut or form female threads or recesses in the surface 25 of the hole 18. This will cause the lag shield 2 exert the maximum pressure y at substantially the point 17 Well Within Haring surface 26 are somewhat exaggerated, as Well as the gripping action of the bolt anchor, for purposes of clearer illus- 1 tration. i

Itis also apparent that different thicknesses of Work can be held by the same bolt anchor Without the lag screw 21 binding before it has snugly secured the Work to the face of the- Wall, partition, block or other support.

Having thus described this invention in connection With an illustrative embodiment thereof to the details of which I do not desire to be limited, except as required by the scopey of the appended claims, What is claimed as new and what is desired to secure by Letters Patent is set forth in the appended claims.

What I claim as my invention and desire to secure by Letters Patent is 1. An article ofmanufacture comprising ak one part lag shield having an open side and provided with an inner inclined expanding surface inclined from near its outer end to a point intermediateits ends and from that point reversely inclined to the inner end of the lag shield.

Y Copies of this patent may be obtained for 2. An` article of manufacture comprising a one part lag shield having an inner inclined f expanding surface inclinedr from near its outer end to a point intermediate `its ends and from that point reversely 'inthe face 14 of the Waller I clined to the inner end of the lag shield and one or more lugs adapted to connect said shield With a cooperating expanding device.

3. An article of manufacture comprising a one part lag shield-having an open side and provided with an inner inclined expanding surface inclined from near its outer end to a point intermediate its ends and from that point reversely inclined to the inner end of the lag shield and one or more lugs adapted to connect said shield with a coperating expanding device.

4. The combination` in a bolt anchor of a one part lag shield having an open side and provided With an inclined bore, from near its outer end to a point intermediate its ends, and from that point reversely inclined to the inner end of the lag shield, and an expanding device adapted to coperate with said inclined surfaces and directly with a support.

5. The combination in a bolt anchor of a one part lag shield having an open side and provided with an inclined bore from near its outer end to a point intermediate its ends,

yand 'from that point reversely inclined to the inner end of the lag shield, and a bolt or fscrew adapted to coperate with said inclined surfaces and directly With a support.

6. An article of manufacture comprising a one part lag shield provided With an inclined bore having interrupted screw threads fora part of its length and a bolt or screw to coperate with the interrupted screw threads, said inclined bore diminishing in diameter to a point intermediate its ends and from thrt point increasing in diameter as it advances toward the other end of theshicld'.

HENRY W. PLEISTER. Witnesses MARY R. RYAN, ELIZABETH J. ROTH.

five cents each, by addressing-the Commissioner of Patents, Washington, D. C. 

